Tire-valve



M. C. SCHWEINERT AND H. P. KRAFT.

TIRE VALVE.

APPLICATION FILED MAR- 24. 1916.

' INVENTORS WITNESSES: e fi W BfAtter'e,

UNITED STATES MAXIMILIKTI CHARLES EEHWEINEB'I',

OF WEST HOBOKEN, OF BIDGEWOOD, NEW JERSEY.

AND HENRY P. KRAFT,

TIRE-VALVE.

Specification of Letters Patent.

Patented Feb. 1, 1921.

Application filed March 24, 1916. Serial No. 86,347.-

T all whom it may concern.

Be it known that we, MAXIMILIAN CHARLES SCHWEINERT and HENRY P.

KRAFT, citizens of the UnitedStates of America, residing in WestHoboken, m the county of Hudson and State of New Jersey, and Ridgewood,in the county of Bergen and State of New Jersey, respectively, haveinvented certain new and useful I-mprovements in Tire-Valves, of whichthe following is a Specification.

his invention relates to tire valves or the like, and aims to providecertain improvements therein.

Tire and similar valves have heretofore been made with a long casing orstem which has been connected to the inner tube or other container whichit is desired to inflate, such casing or stem being of very considerablelength as compared with its diameter, and being designed to inclose theworking parts of the valve. On account of limitations imposed by thewheel rim such casings have been of small external diameterapproximatingfrom one-half to threequarters of an inch. Consequently thebore or passage through the casing has been very small, being in mostcases not over onequarter of an inch in diameter. It has been customaryto form such valve casings of brass or other rust-resisting material forthe reason that they are exposed to wet and moisture and speedily rustif formed of a material which easily oxidizes. This is particularly truewith regard to the internal bore of the casing, since such bore cannotin practice be coated by any ordinary electrolytic process. When acasing is subjected, for instance, to an electro-deposition process thecoating does not enter to any extent the bore of the valve, so that theinternal walls of the bore are left unprotected. Furthermore, theexternal walls of the casing are usually threaded to engage nuts, caps,pump couplings, etc., and an electrically deposited coating isnot'sufiiciently firm and durable to avoid wearing off under suchconditions. use of cheaper metal, such as steel or iron, in themanufacture of such stems.

After careful experiments we have found that itis possible to produce asatisfactory coating not only on the exterior but on the interior boreof a steel or similar valve by the sherardizing method. We have found onthe walls of the These factors have prevented the that we can obtaina'rust-proofcondition long narrow bore by subjeoting the casing to thevapors of ZlIlC or other dust without necessarily packing the bore withsuch dust. Contrary to our experience-with electrodepositing processes.the coating on the interior of the bore is found to be substantiallyequal to the coating on the exterior of the casing, or at leastsufficiently good to prevent rusting under ordinary servlce conditions.Furthermore, this is true not only with regard to the plane walls of theinterior bore, but also with regard to the interior threads and taperedshoulder of the valve casing'of common form. By electro-depositingprocesses it is diflicult if not impossible to produce an adequatecoating on threads even if they are on the exterior of the article beingcoated, while on the interior threads, as before stated, it ispractically impossible.

In the drawings we have illustrated a common form of pneumatic tirevalve in diametrical section, the body of the valve being indicated bythe'reference letter A and the coating by the letter B. It will beobserved that the bore which is lettered C is relatively very long inproportion to its diameter, and usually is formed with an interiorthread D at its top which is designed to engage the seat member of thevalve. The bore is usually formed with a tapered shoulder or seat Ewhich is engaged by a packing carried upon the valve seat to make atight joint between the latter and the casing. In the best constructionsbelow the shoulder E there is located a valve chamber F which is oflarger diameter than the shoulder, and which receives the actual workingparts of the valve, such as the plumger, spring, etc.

In carrying the invention into practice the valve casings with the zincdust or other metallic dust may be placed in a revolving barrel orreceptacle which is heated to a point which is below the fusingtemperature of the metal. As the barrel revolves the dust probablypartly casings, and the coating formed is found to be applied to thevarious crevices formed by the screw-threads, shoulders, etc., as wellas the plain surfaces. It is probable that the zinc vapors enter thepores of the steel and produce something in the nature of an alloyextending to some considerable disenters the bores of the tance belowthe surface of the metal. In

' any event an even and desirable coating is provided.

What we claim is a 1. The method of rust-proofing a pneumatic tire valvecasing having a relatively small elongated bore and an internalscrewthlead which consists in forming a sherardizedcoating on theinterior of the casing.

2. pneumatic valve casing or the like compr sing an elongated strnctu 'eof steel or similar oxidizing material having a comparatively small boreextending throughout the length thereof, and said casing having aninternal coating of vapor-deposited rust- 16 proofing metal.

In witness whereof we have hereunto signed our names in the presence oftwo subscribing witnesses.

MAXIMILIAN CHARLES SCHWEINERT. HENRY P. KRAFT. Witnesses:

GRACE GUNDERMAN, THOMAS F. WALLACE.

